Add more out of line copy ctors for complex classes.

content/common/frame_replication_state.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/frame_replication_state.h"
 #include "third_party/WebKit/public/web/WebSandboxFlags.h"
 #include "third_party/WebKit/public/web/WebTreeScopeType.h"
 
 namespace content {
 
@@ skipping 13 matching lines @@
     : origin(),
       sandbox_flags(sandbox_flags),
       name(name),
       unique_name(unique_name),
       scope(scope),
       should_enforce_strict_mixed_content_checking(
           should_enforce_strict_mixed_content_checking),
       has_potentially_trustworthy_unique_origin(
           has_potentially_trustworthy_unique_origin) {}
 
+FrameReplicationState::FrameReplicationState(
+    const FrameReplicationState& other) = default;
+
 FrameReplicationState::~FrameReplicationState() {
 }
 
 }  // namespace content